export default {
	namespaced: true,

	state: () => ({
		// 每个商品的信息对象，都包含如下 6 个属性：
		// { goods_id, goods_name, goods_price, goods_count, goods_small_logo, goods_state }
		cart: JSON.parse(uni.getStorageSync('cart') || '[]')
	}),

	mutations: {
		addToCart(state, goods) {

			const findResult = state.cart.find(x => x.goods_id === goods.goods_id)

			if (!findResult) {
				state.cart.push(goods)
			} else {
				findResult.goods_count++
			}

			this.commit('m_cart/saveToStorage')
		},

		saveToStorage(state) {
			uni.setStorageSync('cart', JSON.stringify(state.cart))
		},

		updateGoodsState(state, goods) {
			const findResult = state.cart.find(x => x.goods_id === goods.goods_id)

			if (findResult) {
				findResult.goods_state = goods.goods_state
				this.commit('m_cart/saveToStorage')
			}
		},

		updateGoodsCount(state, goods) {
			const findResult = state.cart.find(x => x.goods_id === goods.goods_id)

			if (findResult) {
				// 更新对应商品的数量
				findResult.goods_count = goods.goods_count
				// 持久化存储到本地
				this.commit('m_cart/saveToStorage')
			}
		},

		removeGoodsById(state, goods_id) {
			state.cart = state.cart.filter(x => x.goods_id !== goods_id)
			this.commit('m_cart/saveToStorage')
		},

		updateAllGoodsState(state, newState) {
			state.cart.forEach(x => x.goods_state = newState)

			this.commit('m_cart/saveToStorage')
		}
	},

	getters: {
		total(state) {
			let c = 0

			state.cart.forEach(x => c += x.goods_count)
			return c
		},

		checkedCount(state) {
			return state.cart.filter(x => x.goods_state).reduce((total, item) => total += item.goods_count, 0)
		},

		checkedGoodsAmount(state) {
			return state.cart.filter(x => x.goods_state)
				.reduce((total, item) => total += item.goods_count * item.goods_price, 0)
				.toFixed(2)
		}
	},
}
